1. Field of Use
This invention relates generally to apparatus for producing electrical wire leads. In particular, it relates to apparatus for high-speed production of sets of accurately and identically sized insulated wire leads having electrical terminals on the ends thereof, and especially to a wire lead clamping mechanism for such apparatus.
2. Description of the Prior Art
Various types of apparatus exist for mass production of insulated electrical wire leads having electrical terminals attached to one or both ends of each lead. Such apparatus typically includes a reel of wire, a feed mechanism for drawing a strand of wire from the reel, a severing mechanism for cutting a wire segment of predetermined length from the strand, a conveyor mechanism having releasable conveyor clamps for gripping the wire segment and for conveying it to a wire stripping mechanism wherein one or both ends are stripped of insulation and then to a terminal attachment mechanism wherein electrical terminals are attached to one or both stripped ends of the wire segment, whereupon the finished lead is conveyed to a collecting station and the conveyor clamps open to deposit the finished lead thereat.
The following three U.S. patents, assigned to the same assignee as the present application, disclose apparatus and mechanisms of the aforesaid character. U.S. Pat. Nos. 3,701,301 and 3,918,330, for example, disclose apparatus for manufacturing individual wire leads from a single reel of wire and this apparatus includes a wire feed mechanism employing two counter-reciprocating feed clamps and a conveyor mechanism having releasable conveyor clamps thereon. U.S. Pat. No. 3,703,954 also discloses and claims a conveyor mechanism having releasable conveyor clamps. U.S. Pat. No. 3,274,664 discloses a terminal attachment mechanism for automatically feeding and attaching wire terminals from a continuous ribbon to the ends of successively presented wire segments.
It is desirable to increase the productive capacity of apparatus for producing electrical wire leads and also to reduce the manufacturing costs of such leads. Experience has shown, however, that apparatus constructed to simultaneously process two or more wire segments requires processing mechanisms which are relatively complicated in construction and operation, costly to manufacture, and prone to malfunction during high-speed production runs. For example, in the type of apparatus shown in the aforementioned U.S. Pat. Nos. 3,918,330, 3,701,301, and 3,703,954, each of the conveyor clamps comprises a pair of jaws which extend upwardly and open and close in a vertical plane and are adapted to grip and convey a single wire segment which extends perpendicularly to the aforesaid vertical plane. If an attempt is made to convey two or more wire segments in such a conveyor clamp for simultaneous processing, the wire segments are disposed one above another in a vertical plane and conveyed in a horizontal plane. As a result, the movable operating components in the processing mechanisms (such as cutters, strippers, and terminal attachment mechanisms) must act or move horizontally (i.e., in the same planes of movement of the several wire segments), rather than vertically, in order to have simultaneous access to the several wire segments. As a result, the construction and operation of the processing mechanisms to be used in such apparatus becomes very complicated. Consequently, there has been a practical limit on the quantity of wire leads that can be simultaneously processed and a limit on the speed at which leads can be reliably manufactured. Furthermore, problems of quality control arise in connection with terminal attachment to small gauge wire, such as 27 gauge wire, which need to be overcome, especially in high-speed apparatus.